Officers carried out the planned searches on Saturday night under the Terrorism Act.

The first was in the Poleglass area of west Belfast and the second, in the New Lodge Road area, in the north of the city.

At both addresses, a number of items were taken away for further examination.

A PSNI spokeswoman said the searches were carried out in connection with the murder.

The spokeswoman said: "Police are continuing to appeal for information about the movements of Mr Johnston on the day of the murder and a dark-coloured car that was seen in the area around the time of the incident.

"Anyone with information that could help the investigation should contact detectives on the non-emergency number 101, quoting reference 1192 of 13/2/18 or ask to speak to detectives at the incident room in Musgrave.

"Alternatively, information can also be provided to the independent charity Crimestoppers on 0800 555 111 which is 100% anonymous and gives people the power to speak up and stop crime."

Last week police issued an appeal for anyone who witnessed a man wearing a blue coat with fur around the hood make off from the scene.

He got into a black car with tinted windows which drove away.

Police have said two gunmen were involved in the murder and that dissident republican activity is one of the lines of enquiry they are pursuing.